The 'S' and Marper judgement in the European Court of Human Rights ruled 'blanket and indiscriminate' retention of DNA unlawful. The government's proposal to retain the DNA profiles of innocent people on a criminal database for 6 years fails to address the key legal principle: that any retention at all of DNA from those uncharged or unconvicted of a crime is a breach of privacy rights, and needs justification.

The proposals are calculated to change current practice as little as possible, and to keep building up the National DNA Database, already by far the largest in the world. But while Home Office figures suggest that testing more DNA from crime scenes has helped to solve more crimes, massively expanding the number of individuals with records on the database has not.

A far more proportionate and practical approach would be to adopt the Scottish system, where DNA profiles from a small number of innocent people are allowed to be retained for three years (or exceptionally five, on application to a sheriff, and with right of appeal) in cases where the person is arrested for a relevant sexual or violent crime, and proceedings are commenced and dropped or result in a not guilty verdict.

Just a few hundred individuals' DNA profiles are held under this legislation, as opposed to almost a million people in England and Wales.